#include "Keypad.h"
 
const byte ROWS = 4; //four rows
const byte COLS = 4; //four columns
//define the cymbols on the buttons of the keypads
char hexaKeys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}
};
byte rowPins[ROWS] = { 8, 9,10,11}; //connect to the row pinouts of the keypad
byte colPins[COLS] = { 4, 5, 6, 7}; //connect to the column pinouts of the keypad
 
//initialize an instance of class NewKeypad
Keypad customKeypad = Keypad( makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS); 
 
void setup(){
  Serial.begin(9600);
}
   
void loop(){
  char customKey = customKeypad.getKey();
   
  if (customKey){
    Serial.println(customKey);
  }
}
